In one aspect, this invention relates to moveable shelters. In another aspect, this invention relates to detachable dolly units which can be used to move large structures.
It has become common to construct shelters for medical or electronic equipment as rigid structures which sit on a base structure but can be moved from place to place. To move one of the structures, two dolly units are moved into position with one at the front and one at the rear of the shelter. Each dolly must be positioned and tilted so a lifting prong engages a portion of the shelter near its lower edge. Fasteners are then used to attach the dolly to the end of the shelter and the dollys righted to lift the shelter. One of the dollys has a tow bar which can be attached to a towing vehicle and the shelter, with a dolly attached front and rear, can be moved to a new location. The dollys are removed and the shelter is firmly positioned on the ground.
The shelters commonly in use for medical and electrical applications have increased in size and weight to accommodate new and improved technology. Consequently, dollys suitable for lifting the shelters off the ground and supporting them for transport have also had to increase in size and weight. The increased weight makes the dollys more difficult to maneuver into position. Positioning of the dolly is particularly important since the fasteners must be accurately aligned with complimentary fastening means on the shelter to hold the unit together during transportation. Because of the dolly's weight, it requires two or more people to position the dolly and misalignments are frequent. Generally, it has been found that 20-30 minutes are required to align and fasten a dolly to a shelter. Positioning is a particular problem since if the fasteners do not mate, the dolly must be backed out of engagement with the shelter and repositioned for another alignment attempt. Such attempts consume valuable time and are fatiguing to the individuals who are positioning the dolly.
It would be desirable to have a dolly which can easily be positioned at the end of a shelter to facilitate the alignment and attachment of the dolly to the shelter. This would decrease the time necessary to position the dolly and for attachment to the shelter.